Sheet metal working tool for automobile bodies



April 28, 1959 w. A. STEVENSON 2,884,043

. SHEET METAL WORKING TOOL FOR AUTOMOBILE BODIES Filed Feb. 2, 195aWilliam A. SfeVenson INVENTOR.

SHEET METAL WORKING TOOL FOR AUTOMOBILE BODIES William A. Stevenson,Spokane, Wash. Application February 2, 1953, Serial No. 334,627 2Claims. 01. 153-39 This invention is .a sheet metal working tool forautomobile bodies and is an improvement over the invention of William E.Lund, Serial No. 244,555, filed August 31, 1.951, for Pecking Tool, nowU.S. Patent No. 2,694,435 issued November 16, 1954 of which I :am theassignee of the full right, title and interest.

An object of this invention is to provide an inexpensive sheet metalworking tool for the automobile body-repair industry.

- Another object of the invention is to provide a sheet metalworkingtool which comprises a minimum numberof parts arranged in such away as to be very-inexpensive to'manufacture and not liable to becomeinoperative.

Another object of the invention lies in the provision of a sheet metalworking tool which has a reciprocable hammer therein and a cushioningmeans rearwardly of the hammer for retarding the rearward movement ofthe hammer and preventing its striking the rear closure for the tool.

Another object of the invention lies in the provision of an improvedreciprocating hammer for tools of the class disclosed.

These and other objects of the invention will become apparent during thecourse of the following description.

In the accompanying drawings, forming a part of this specification, andin which like numerals are employed to designate like parts,

Figure 1 is a longitudinal cross section taken through an embodiment ofthe invention;

Figure 2 is a perspective view of the head for associafion with thetool;

Figure 3 is :a perspective view of the peen .adapted to be pivotallycarried by the head;

Figure 4 is a longitudinal fragmentary cross section of a modified formof the tool showing parts in elevation; and

Figure 5 is an exploded isometric view of an improved hammer.

Referring now more particularly to the drawing, I have shown the tool ashaving a head which is provided with a reduced externally threadedportion 11 and an enlarged portion 12, which together define a shoulder13 intermediate the two portions. The enlarged portion 12 is providedwith flattened faces 14 diametrically disposed with respect to eachother to provide means for securing a wrench to the head for applicationand removal thereof. A longitudinally extending slot 15 is milled in thehead and communicates with a transversely extending slot 16 milleddiametrically of the reduced portion 11 of the head. The slot isprovided to contain the pivotal peen 17. Axially aligned holes 13-18 aredrilled through the reduced portion of the head parallel with itsdiameter and offset therefrom. A pivot pin 19 is passed through theholes 18-18 and through the pivot aperture 20 of peen 17 and thuspivotally mounts the peen in the head 10.

The peen is formed with a flat body 21 shaped in an obtuse angle havingthe pivot aperture 20 in the body at the apex of the angle. One leg'ofthe angle constitutes an anvil 22 and the other leg supports a metalworking lip 23 which is disposed substantially in parallel offsetrelation to the anvil leg. The lip 23 is formed wedge- Shaped and hasits side corners bevelled as at 24 and the" peen 17 is tempered toprovide a metalworking tool which will not be distorted by working sheetmetal in The lip 23 may have othersh-apes. if.-

automobile bodies. desirable. The head is threadedly engaged in theforward end of the cylindrical or tubular body 25 which is internallythreaded at 26. The body is provided with air-escape ports 27 drilledtherein. A reciprocable hammer 28 is slidably carried within the bodyand is of substantially the same diameter as the inside diameter of thebody 25,

forcing the 'lip 23 outwardly of the head for the purposeof workingsheet metal. I e

The rear face 31 of the hammer has an axial boss 32 which is providedwith a transverse bore 33 and constitutes an eye carried by the rearface 31 of the hammer.

A resilient rubber washer 52 encircles the boss 32'1and is therebysecured in covering relation to the 'rear face 31.

The rear end of the body 25 is also internally threaded as at 34' and aclosure or plug 34, having a reduced externally threaded portion 35 andan enlarged outer portion 36 defining a shoulder 37, is threadedlyengaged in closing relation to the rear end of the body 25. The closure34 is provided with a further reduced forwardly projecting extension 51which is formed to provide ade quate length to the closure 34 so thatthe axial bore 39 is of a length to adapt it to completely contain thetension spring 40, which has its forward end 41 hooked in the eye ofhammer 28. The rear end of the spring is secured about a pin 42 havingits ends carried in spaced transverse openings 43 drilled in the closure34. The bore 39 is internally threaded at its outer end to receive aconduit 44 which contains a valve (not shown) and communicates thehammer with a fluid pressure sup ply (not shown).

The shoulder 37 of the closure 34 and the shoulder 13 of the head 10bear against the edge end faces of the body 25 to secure the head andclosure against rotary movement relative to the body. Theclosure 34 isalso provided with the diametrically opposed faces 14 upon which awrench may be used to place or remove the parts.

In Figure 4 l have shown a modified form of the hammer which has thesame body 25 excepting that the exhaust ports 27 may be omitted, as airforced by the for ward movement of hammer 28 will pass through themilled slots 15 and 16 to the atmosphere.

A spring 45 of the expansion type is placed in the body forwardly of thehammer and it bears against the inside face of the reduced portion 11 ofthe head 10 and against the hammer. Since it is necessary for the hammerto shift forwardly sufficient distance to strike the anvil 22, thehammer 46 has been provided with a reduced forward end portion 47providing a space between the forward end portion of the hammer 46 andthe body 25 to receive the expansion spring 45. The rear end 48 of thehammer is of substantially the same diameter as the internal diameter ofthe body, being reduced only enough to provide free reciprocablemovement of the hammer, and this portion may be provided by turning thehammer from one piece of stock or by pressing the sleeve indicated at 49in Figures 4 and 5 onto the reduced por E eri s AP!" 3 5.

tio'n 4'7. This construction forms a shoulder 50 intermediate theforward reduced portion and the rear portion 48 and provides a bearingsurface for expansion spring 45.

, Spaced forwardly from the closure 34", indicated in Figure 4, arevents 51. The closure 34" is of the same construction as the closure 34excepting the forwardly projecting extension 38 is omitted and theopenings 43 are not formed therein.

The axial bore 39, having internal threads, is necessary to communicatethe tool with the source of fluid under pressure. As the valve in theconduit 44 is opened, the fluid under pressure drives the hammer 46 or28 forwardly striking the anvil 22 and causing the peen 17 to work thesheet metal. When the valve is closed, the resilient spring 40 or 45returns the hammer, its rearward movement being cushioned by the meansintermediate the hammer and the closure 34 or 34". In Figure 1, themeans is the rubber washer 52 and in Figure 5 the means takes the formof the vents 51 being spaced forwardly from the closure 34". As thehammer moves rearwardly its enlarged portion 48 closes the vents 51 andthe air escape is eliminated, thus a pressure is built up behind thehammer and cushions the return movement of the hammer intermediate thehammer and the closure 34".

Having thus described my invention, I claim:

1. A sheet metal working tool comprising a tubular body having a head atits forward end carrying a movable metal working peen; a hammer slidablein said body toward and away from said head; an eye on the rear 'aeeaoes4 end of said hammer; a closure adapted to communicate the body with avalved fluid pressure supply and closing the body at the end opposed tosaid head; a forwardly projecting reduced extension on said closurecoaxial with the body and serving as an abutment; said closure beingaxially bored to define an elongated housing; a diametrically disposedpin extending through the bore adjacent the rear end; a tension springsecured at one end to the pin and normally confined to the housing andhaving its other end secured in said eye; and a rubber cushioning devicedisposed between the hammer and the abutment. 2. The invention asdefined in claim 5, wherein the peen comprises a flat body shaped in anobtuse angle and having a pivot aperture in the body at the apex of theangle, one leg of the angle constituting an anvil and the other legsupporting a metal working lip disposed substantially in parallel offsetrelation to the anvil leg.

References Cited in the file of this patent UNITED STATES PATENTS410,935 Schmidt Sept. 10, 1889 1,798,378 Kott Mar. 31, 1931 2,263,952Mercorelli Nov. 25, 1941 2,483,626 Daku Oct. 4, 1949 2,490,254 CasazzaDec. 6, 1949 2,526,380 Mathews Oct. 17, 1950 2,534,525 Molloy Dec. 19,1950 2,694,435 Lund Nov. 16, 1954 2,714,918 Hopkins Aug. 9, 1955

